crackling sound out of right speaker

Are you using jumper cables betwenn posts? If so, be sure the jumper's posts are tightly screwed down.

I had a very similar experience where i was getting a crackling/interference/whistley sort of noise on the left side and it was driving me bonkers. After all of the cable switching I read about this phenomena called Tube microphony. Since I have a tube preamp, I found that that the tubes for the left side were the culprit. I hope all goes well with your diagnosis because I know you won't stop til you have this thing sorted out. Keep us all posted.

Polk and Vinylmad, The OP's problem has to be in his Right speaker or the cable leading to it. That's been settled, I think. Good thought by Miner to check any jumper cable that is being used to connect among terminals at the rear of that speaker. A loose connection could conceivably be a factor, either inside the speaker cabinet or at the speaker inputs.

I brought the pre, amp and right speaker into the shop, the owner assured me it wasn't the speaker, he believes it's the input tubes in my amp, he loaned me a integrated amp and after hooking it up, the right speaker sounds fine. ill let everyone know what the actual culprit is as soon as I can.
thanks for all your suggestions

The owner assured me it wasn't the speaker, he believes it's the input tubes in my amp, he loaned me a integrated amp and after hooking it up, the right speaker sounds fine.

That seems irreconcilable with the fact that switching the L & R connections at the amp outputs did not cause the problem to move to the left speaker. Did he offer any comments on that?

Regards,
-- Al